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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * PowerMac G5 SMU driver4 *5 * Copyright 2004 J. Mayer <l_indien@magic.fr>6 * Copyright 2005 Benjamin Herrenschmidt, IBM Corp.7 */8 9/*10 * TODO:11 * - maybe add timeout to commands ?12 * - blocking version of time functions13 * - polling version of i2c commands (including timer that works with14 * interrupts off)15 * - maybe avoid some data copies with i2c by directly using the smu cmd16 * buffer and a lower level internal interface17 * - understand SMU -> CPU events and implement reception of them via18 * the userland interface19 */20 21#include <linux/types.h>22#include <linux/kernel.h>23#include <linux/device.h>24#include <linux/dmapool.h>25#include <linux/memblock.h>26#include <linux/vmalloc.h>27#include <linux/highmem.h>28#include <linux/jiffies.h>29#include <linux/interrupt.h>30#include <linux/rtc.h>31#include <linux/completion.h>32#include <linux/miscdevice.h>33#include <linux/delay.h>34#include <linux/poll.h>35#include <linux/mutex.h>36#include <linux/of.h>37#include <linux/of_address.h>38#include <linux/of_irq.h>39#include <linux/of_platform.h>40#include <linux/platform_device.h>41#include <linux/slab.h>42#include <linux/sched/signal.h>43 44#include <asm/byteorder.h>45#include <asm/io.h>46#include <asm/machdep.h>47#include <asm/pmac_feature.h>48#include <asm/smu.h>49#include <asm/sections.h>50#include <linux/uaccess.h>51 52#define VERSION "0.7"53#define AUTHOR "(c) 2005 Benjamin Herrenschmidt, IBM Corp."54 55#undef DEBUG_SMU56 57#ifdef DEBUG_SMU58#define DPRINTK(fmt, args...) do { printk(KERN_DEBUG fmt , ##args); } while (0)59#else60#define DPRINTK(fmt, args...) do { } while (0)61#endif62 63/*64 * This is the command buffer passed to the SMU hardware65 */66#define SMU_MAX_DATA 25467 68struct smu_cmd_buf {69 u8 cmd;70 u8 length;71 u8 data[SMU_MAX_DATA];72};73 74struct smu_device {75 spinlock_t lock;76 struct device_node *of_node;77 struct platform_device *of_dev;78 int doorbell; /* doorbell gpio */79 u32 __iomem *db_buf; /* doorbell buffer */80 struct device_node *db_node;81 unsigned int db_irq;82 int msg;83 struct device_node *msg_node;84 unsigned int msg_irq;85 struct smu_cmd_buf *cmd_buf; /* command buffer virtual */86 u32 cmd_buf_abs; /* command buffer absolute */87 struct list_head cmd_list;88 struct smu_cmd *cmd_cur; /* pending command */89 int broken_nap;90 struct list_head cmd_i2c_list;91 struct smu_i2c_cmd *cmd_i2c_cur; /* pending i2c command */92 struct timer_list i2c_timer;93};94 95/*96 * I don't think there will ever be more than one SMU, so97 * for now, just hard code that98 */99static DEFINE_MUTEX(smu_mutex);100static struct smu_device *smu;101static DEFINE_MUTEX(smu_part_access);102static int smu_irq_inited;103static unsigned long smu_cmdbuf_abs;104 105static void smu_i2c_retry(struct timer_list *t);106 107/*108 * SMU driver low level stuff109 */110 111static void smu_start_cmd(void)112{113 unsigned long faddr, fend;114 struct smu_cmd *cmd;115 116 if (list_empty(&smu->cmd_list))117 return;118 119 /* Fetch first command in queue */120 cmd = list_entry(smu->cmd_list.next, struct smu_cmd, link);121 smu->cmd_cur = cmd;122 list_del(&cmd->link);123 124 DPRINTK("SMU: starting cmd %x, %d bytes data\n", cmd->cmd,125 cmd->data_len);126 DPRINTK("SMU: data buffer: %8ph\n", cmd->data_buf);127 128 /* Fill the SMU command buffer */129 smu->cmd_buf->cmd = cmd->cmd;130 smu->cmd_buf->length = cmd->data_len;131 memcpy(smu->cmd_buf->data, cmd->data_buf, cmd->data_len);132 133 /* Flush command and data to RAM */134 faddr = (unsigned long)smu->cmd_buf;135 fend = faddr + smu->cmd_buf->length + 2;136 flush_dcache_range(faddr, fend);137 138 139 /* We also disable NAP mode for the duration of the command140 * on U3 based machines.141 * This is slightly racy as it can be written back to 1 by a sysctl142 * but that never happens in practice. There seem to be an issue with143 * U3 based machines such as the iMac G5 where napping for the144 * whole duration of the command prevents the SMU from fetching it145 * from memory. This might be related to the strange i2c based146 * mechanism the SMU uses to access memory.147 */148 if (smu->broken_nap)149 powersave_nap = 0;150 151 /* This isn't exactly a DMA mapping here, I suspect152 * the SMU is actually communicating with us via i2c to the153 * northbridge or the CPU to access RAM.154 */155 writel(smu->cmd_buf_abs, smu->db_buf);156 157 /* Ring the SMU doorbell */158 pmac_do_feature_call(PMAC_FTR_WRITE_GPIO, NULL, smu->doorbell, 4);159}160 161 162static irqreturn_t smu_db_intr(int irq, void *arg)163{164 unsigned long flags;165 struct smu_cmd *cmd;166 void (*done)(struct smu_cmd *cmd, void *misc) = NULL;167 void *misc = NULL;168 u8 gpio;169 int rc = 0;170 171 /* SMU completed the command, well, we hope, let's make sure172 * of it173 */174 spin_lock_irqsave(&smu->lock, flags);175 176 gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell);177 if ((gpio & 7) != 7) {178 spin_unlock_irqrestore(&smu->lock, flags);179 return IRQ_HANDLED;180 }181 182 cmd = smu->cmd_cur;183 smu->cmd_cur = NULL;184 if (cmd == NULL)185 goto bail;186 187 if (rc == 0) {188 unsigned long faddr;189 int reply_len;190 u8 ack;191 192 /* CPU might have brought back the cache line, so we need193 * to flush again before peeking at the SMU response. We194 * flush the entire buffer for now as we haven't read the195 * reply length (it's only 2 cache lines anyway)196 */197 faddr = (unsigned long)smu->cmd_buf;198 flush_dcache_range(faddr, faddr + 256);199 200 /* Now check ack */201 ack = (~cmd->cmd) & 0xff;202 if (ack != smu->cmd_buf->cmd) {203 DPRINTK("SMU: incorrect ack, want %x got %x\n",204 ack, smu->cmd_buf->cmd);205 rc = -EIO;206 }207 reply_len = rc == 0 ? smu->cmd_buf->length : 0;208 DPRINTK("SMU: reply len: %d\n", reply_len);209 if (reply_len > cmd->reply_len) {210 printk(KERN_WARNING "SMU: reply buffer too small,"211 "got %d bytes for a %d bytes buffer\n",212 reply_len, cmd->reply_len);213 reply_len = cmd->reply_len;214 }215 cmd->reply_len = reply_len;216 if (cmd->reply_buf && reply_len)217 memcpy(cmd->reply_buf, smu->cmd_buf->data, reply_len);218 }219 220 /* Now complete the command. Write status last in order as we lost221 * ownership of the command structure as soon as it's no longer -1222 */223 done = cmd->done;224 misc = cmd->misc;225 mb();226 cmd->status = rc;227 228 /* Re-enable NAP mode */229 if (smu->broken_nap)230 powersave_nap = 1;231 bail:232 /* Start next command if any */233 smu_start_cmd();234 spin_unlock_irqrestore(&smu->lock, flags);235 236 /* Call command completion handler if any */237 if (done)238 done(cmd, misc);239 240 /* It's an edge interrupt, nothing to do */241 return IRQ_HANDLED;242}243 244 245static irqreturn_t smu_msg_intr(int irq, void *arg)246{247 /* I don't quite know what to do with this one, we seem to never248 * receive it, so I suspect we have to arm it someway in the SMU249 * to start getting events that way.250 */251 252 printk(KERN_INFO "SMU: message interrupt !\n");253 254 /* It's an edge interrupt, nothing to do */255 return IRQ_HANDLED;256}257 258 259/*260 * Queued command management.261 *262 */263 264int smu_queue_cmd(struct smu_cmd *cmd)265{266 unsigned long flags;267 268 if (smu == NULL)269 return -ENODEV;270 if (cmd->data_len > SMU_MAX_DATA ||271 cmd->reply_len > SMU_MAX_DATA)272 return -EINVAL;273 274 cmd->status = 1;275 spin_lock_irqsave(&smu->lock, flags);276 list_add_tail(&cmd->link, &smu->cmd_list);277 if (smu->cmd_cur == NULL)278 smu_start_cmd();279 spin_unlock_irqrestore(&smu->lock, flags);280 281 /* Workaround for early calls when irq isn't available */282 if (!smu_irq_inited || !smu->db_irq)283 smu_spinwait_cmd(cmd);284 285 return 0;286}287EXPORT_SYMBOL(smu_queue_cmd);288 289 290int smu_queue_simple(struct smu_simple_cmd *scmd, u8 command,291 unsigned int data_len,292 void (*done)(struct smu_cmd *cmd, void *misc),293 void *misc, ...)294{295 struct smu_cmd *cmd = &scmd->cmd;296 va_list list;297 int i;298 299 if (data_len > sizeof(scmd->buffer))300 return -EINVAL;301 302 memset(scmd, 0, sizeof(*scmd));303 cmd->cmd = command;304 cmd->data_len = data_len;305 cmd->data_buf = scmd->buffer;306 cmd->reply_len = sizeof(scmd->buffer);307 cmd->reply_buf = scmd->buffer;308 cmd->done = done;309 cmd->misc = misc;310 311 va_start(list, misc);312 for (i = 0; i < data_len; ++i)313 scmd->buffer[i] = (u8)va_arg(list, int);314 va_end(list);315 316 return smu_queue_cmd(cmd);317}318EXPORT_SYMBOL(smu_queue_simple);319 320 321void smu_poll(void)322{323 u8 gpio;324 325 if (smu == NULL)326 return;327 328 gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell);329 if ((gpio & 7) == 7)330 smu_db_intr(smu->db_irq, smu);331}332EXPORT_SYMBOL(smu_poll);333 334 335void smu_done_complete(struct smu_cmd *cmd, void *misc)336{337 struct completion *comp = misc;338 339 complete(comp);340}341EXPORT_SYMBOL(smu_done_complete);342 343 344void smu_spinwait_cmd(struct smu_cmd *cmd)345{346 while(cmd->status == 1)347 smu_poll();348}349EXPORT_SYMBOL(smu_spinwait_cmd);350 351 352/* RTC low level commands */353static inline int bcd2hex (int n)354{355 return (((n & 0xf0) >> 4) * 10) + (n & 0xf);356}357 358 359static inline int hex2bcd (int n)360{361 return ((n / 10) << 4) + (n % 10);362}363 364 365static inline void smu_fill_set_rtc_cmd(struct smu_cmd_buf *cmd_buf,366 struct rtc_time *time)367{368 cmd_buf->cmd = 0x8e;369 cmd_buf->length = 8;370 cmd_buf->data[0] = 0x80;371 cmd_buf->data[1] = hex2bcd(time->tm_sec);372 cmd_buf->data[2] = hex2bcd(time->tm_min);373 cmd_buf->data[3] = hex2bcd(time->tm_hour);374 cmd_buf->data[4] = time->tm_wday;375 cmd_buf->data[5] = hex2bcd(time->tm_mday);376 cmd_buf->data[6] = hex2bcd(time->tm_mon) + 1;377 cmd_buf->data[7] = hex2bcd(time->tm_year - 100);378}379 380 381int smu_get_rtc_time(struct rtc_time *time, int spinwait)382{383 struct smu_simple_cmd cmd;384 int rc;385 386 if (smu == NULL)387 return -ENODEV;388 389 memset(time, 0, sizeof(struct rtc_time));390 rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 1, NULL, NULL,391 SMU_CMD_RTC_GET_DATETIME);392 if (rc)393 return rc;394 smu_spinwait_simple(&cmd);395 396 time->tm_sec = bcd2hex(cmd.buffer[0]);397 time->tm_min = bcd2hex(cmd.buffer[1]);398 time->tm_hour = bcd2hex(cmd.buffer[2]);399 time->tm_wday = bcd2hex(cmd.buffer[3]);400 time->tm_mday = bcd2hex(cmd.buffer[4]);401 time->tm_mon = bcd2hex(cmd.buffer[5]) - 1;402 time->tm_year = bcd2hex(cmd.buffer[6]) + 100;403 404 return 0;405}406 407 408int smu_set_rtc_time(struct rtc_time *time, int spinwait)409{410 struct smu_simple_cmd cmd;411 int rc;412 413 if (smu == NULL)414 return -ENODEV;415 416 rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 8, NULL, NULL,417 SMU_CMD_RTC_SET_DATETIME,418 hex2bcd(time->tm_sec),419 hex2bcd(time->tm_min),420 hex2bcd(time->tm_hour),421 time->tm_wday,422 hex2bcd(time->tm_mday),423 hex2bcd(time->tm_mon) + 1,424 hex2bcd(time->tm_year - 100));425 if (rc)426 return rc;427 smu_spinwait_simple(&cmd);428 429 return 0;430}431 432 433void smu_shutdown(void)434{435 struct smu_simple_cmd cmd;436 437 if (smu == NULL)438 return;439 440 if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 9, NULL, NULL,441 'S', 'H', 'U', 'T', 'D', 'O', 'W', 'N', 0))442 return;443 smu_spinwait_simple(&cmd);444 for (;;)445 ;446}447 448 449void smu_restart(void)450{451 struct smu_simple_cmd cmd;452 453 if (smu == NULL)454 return;455 456 if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 8, NULL, NULL,457 'R', 'E', 'S', 'T', 'A', 'R', 'T', 0))458 return;459 smu_spinwait_simple(&cmd);460 for (;;)461 ;462}463 464 465int smu_present(void)466{467 return smu != NULL;468}469EXPORT_SYMBOL(smu_present);470 471 472int __init smu_init (void)473{474 struct device_node *np;475 u64 data;476 int ret = 0;477 478 np = of_find_node_by_type(NULL, "smu");479 if (np == NULL)480 return -ENODEV;481 482 printk(KERN_INFO "SMU: Driver %s %s\n", VERSION, AUTHOR);483 484 /*485 * SMU based G5s need some memory below 2Gb. Thankfully this is486 * called at a time where memblock is still available.487 */488 smu_cmdbuf_abs = memblock_phys_alloc_range(4096, 4096, 0, 0x80000000UL);489 if (smu_cmdbuf_abs == 0) {490 printk(KERN_ERR "SMU: Command buffer allocation failed !\n");491 ret = -EINVAL;492 goto fail_np;493 }494 495 smu = memblock_alloc(sizeof(struct smu_device), SMP_CACHE_BYTES);496 if (!smu)497 panic("%s: Failed to allocate %zu bytes\n", __func__,498 sizeof(struct smu_device));499 500 spin_lock_init(&smu->lock);501 INIT_LIST_HEAD(&smu->cmd_list);502 INIT_LIST_HEAD(&smu->cmd_i2c_list);503 smu->of_node = np;504 smu->db_irq = 0;505 smu->msg_irq = 0;506 507 /* smu_cmdbuf_abs is in the low 2G of RAM, can be converted to a508 * 32 bits value safely509 */510 smu->cmd_buf_abs = (u32)smu_cmdbuf_abs;511 smu->cmd_buf = __va(smu_cmdbuf_abs);512 513 smu->db_node = of_find_node_by_name(NULL, "smu-doorbell");514 if (smu->db_node == NULL) {515 printk(KERN_ERR "SMU: Can't find doorbell GPIO !\n");516 ret = -ENXIO;517 goto fail_bootmem;518 }519 if (of_property_read_reg(smu->db_node, 0, &data, NULL)) {520 printk(KERN_ERR "SMU: Can't find doorbell GPIO address !\n");521 ret = -ENXIO;522 goto fail_db_node;523 }524 525 /* Current setup has one doorbell GPIO that does both doorbell526 * and ack. GPIOs are at 0x50, best would be to find that out527 * in the device-tree though.528 */529 smu->doorbell = data;530 if (smu->doorbell < 0x50)531 smu->doorbell += 0x50;532 533 /* Now look for the smu-interrupt GPIO */534 do {535 smu->msg_node = of_find_node_by_name(NULL, "smu-interrupt");536 if (smu->msg_node == NULL)537 break;538 if (of_property_read_reg(smu->msg_node, 0, &data, NULL)) {539 of_node_put(smu->msg_node);540 smu->msg_node = NULL;541 break;542 }543 smu->msg = data;544 if (smu->msg < 0x50)545 smu->msg += 0x50;546 } while(0);547 548 /* Doorbell buffer is currently hard-coded, I didn't find a proper549 * device-tree entry giving the address. Best would probably to use550 * an offset for K2 base though, but let's do it that way for now.551 */552 smu->db_buf = ioremap(0x8000860c, 0x1000);553 if (smu->db_buf == NULL) {554 printk(KERN_ERR "SMU: Can't map doorbell buffer pointer !\n");555 ret = -ENXIO;556 goto fail_msg_node;557 }558 559 /* U3 has an issue with NAP mode when issuing SMU commands */560 smu->broken_nap = pmac_get_uninorth_variant() < 4;561 if (smu->broken_nap)562 printk(KERN_INFO "SMU: using NAP mode workaround\n");563 564 sys_ctrler = SYS_CTRLER_SMU;565 return 0;566 567fail_msg_node:568 of_node_put(smu->msg_node);569fail_db_node:570 of_node_put(smu->db_node);571fail_bootmem:572 memblock_free(smu, sizeof(struct smu_device));573 smu = NULL;574fail_np:575 of_node_put(np);576 return ret;577}578 579 580static int smu_late_init(void)581{582 if (!smu)583 return 0;584 585 timer_setup(&smu->i2c_timer, smu_i2c_retry, 0);586 587 if (smu->db_node) {588 smu->db_irq = irq_of_parse_and_map(smu->db_node, 0);589 if (!smu->db_irq)590 printk(KERN_ERR "smu: failed to map irq for node %pOF\n",591 smu->db_node);592 }593 if (smu->msg_node) {594 smu->msg_irq = irq_of_parse_and_map(smu->msg_node, 0);595 if (!smu->msg_irq)596 printk(KERN_ERR "smu: failed to map irq for node %pOF\n",597 smu->msg_node);598 }599 600 /*601 * Try to request the interrupts602 */603 604 if (smu->db_irq) {605 if (request_irq(smu->db_irq, smu_db_intr,606 IRQF_SHARED, "SMU doorbell", smu) < 0) {607 printk(KERN_WARNING "SMU: can't "608 "request interrupt %d\n",609 smu->db_irq);610 smu->db_irq = 0;611 }612 }613 614 if (smu->msg_irq) {615 if (request_irq(smu->msg_irq, smu_msg_intr,616 IRQF_SHARED, "SMU message", smu) < 0) {617 printk(KERN_WARNING "SMU: can't "618 "request interrupt %d\n",619 smu->msg_irq);620 smu->msg_irq = 0;621 }622 }623 624 smu_irq_inited = 1;625 return 0;626}627/* This has to be before arch_initcall as the low i2c stuff relies on the628 * above having been done before we reach arch_initcalls629 */630core_initcall(smu_late_init);631 632/*633 * sysfs visibility634 */635 636static void smu_expose_childs(struct work_struct *unused)637{638 struct device_node *np;639 640 for_each_child_of_node(smu->of_node, np)641 if (of_device_is_compatible(np, "smu-sensors"))642 of_platform_device_create(np, "smu-sensors",643 &smu->of_dev->dev);644}645 646static DECLARE_WORK(smu_expose_childs_work, smu_expose_childs);647 648static int smu_platform_probe(struct platform_device* dev)649{650 if (!smu)651 return -ENODEV;652 smu->of_dev = dev;653 654 /*655 * Ok, we are matched, now expose all i2c busses. We have to defer656 * that unfortunately or it would deadlock inside the device model657 */658 schedule_work(&smu_expose_childs_work);659 660 return 0;661}662 663static const struct of_device_id smu_platform_match[] =664{665 {666 .type = "smu",667 },668 {},669};670 671static struct platform_driver smu_of_platform_driver =672{673 .driver = {674 .name = "smu",675 .of_match_table = smu_platform_match,676 },677 .probe = smu_platform_probe,678};679 680static int __init smu_init_sysfs(void)681{682 /*683 * For now, we don't power manage machines with an SMU chip,684 * I'm a bit too far from figuring out how that works with those685 * new chipsets, but that will come back and bite us686 */687 platform_driver_register(&smu_of_platform_driver);688 return 0;689}690 691device_initcall(smu_init_sysfs);692 693struct platform_device *smu_get_ofdev(void)694{695 if (!smu)696 return NULL;697 return smu->of_dev;698}699 700EXPORT_SYMBOL_GPL(smu_get_ofdev);701 702/*703 * i2c interface704 */705 706static void smu_i2c_complete_command(struct smu_i2c_cmd *cmd, int fail)707{708 void (*done)(struct smu_i2c_cmd *cmd, void *misc) = cmd->done;709 void *misc = cmd->misc;710 unsigned long flags;711 712 /* Check for read case */713 if (!fail && cmd->read) {714 if (cmd->pdata[0] < 1)715 fail = 1;716 else717 memcpy(cmd->info.data, &cmd->pdata[1],718 cmd->info.datalen);719 }720 721 DPRINTK("SMU: completing, success: %d\n", !fail);722 723 /* Update status and mark no pending i2c command with lock724 * held so nobody comes in while we dequeue an eventual725 * pending next i2c command726 */727 spin_lock_irqsave(&smu->lock, flags);728 smu->cmd_i2c_cur = NULL;729 wmb();730 cmd->status = fail ? -EIO : 0;731 732 /* Is there another i2c command waiting ? */733 if (!list_empty(&smu->cmd_i2c_list)) {734 struct smu_i2c_cmd *newcmd;735 736 /* Fetch it, new current, remove from list */737 newcmd = list_entry(smu->cmd_i2c_list.next,738 struct smu_i2c_cmd, link);739 smu->cmd_i2c_cur = newcmd;740 list_del(&cmd->link);741 742 /* Queue with low level smu */743 list_add_tail(&cmd->scmd.link, &smu->cmd_list);744 if (smu->cmd_cur == NULL)745 smu_start_cmd();746 }747 spin_unlock_irqrestore(&smu->lock, flags);748 749 /* Call command completion handler if any */750 if (done)751 done(cmd, misc);752 753}754 755 756static void smu_i2c_retry(struct timer_list *unused)757{758 struct smu_i2c_cmd *cmd = smu->cmd_i2c_cur;759 760 DPRINTK("SMU: i2c failure, requeuing...\n");761 762 /* requeue command simply by resetting reply_len */763 cmd->pdata[0] = 0xff;764 cmd->scmd.reply_len = sizeof(cmd->pdata);765 smu_queue_cmd(&cmd->scmd);766}767 768 769static void smu_i2c_low_completion(struct smu_cmd *scmd, void *misc)770{771 struct smu_i2c_cmd *cmd = misc;772 int fail = 0;773 774 DPRINTK("SMU: i2c compl. stage=%d status=%x pdata[0]=%x rlen: %x\n",775 cmd->stage, scmd->status, cmd->pdata[0], scmd->reply_len);776 777 /* Check for possible status */778 if (scmd->status < 0)779 fail = 1;780 else if (cmd->read) {781 if (cmd->stage == 0)782 fail = cmd->pdata[0] != 0;783 else784 fail = cmd->pdata[0] >= 0x80;785 } else {786 fail = cmd->pdata[0] != 0;787 }788 789 /* Handle failures by requeuing command, after 5ms interval790 */791 if (fail && --cmd->retries > 0) {792 DPRINTK("SMU: i2c failure, starting timer...\n");793 BUG_ON(cmd != smu->cmd_i2c_cur);794 if (!smu_irq_inited) {795 mdelay(5);796 smu_i2c_retry(NULL);797 return;798 }799 mod_timer(&smu->i2c_timer, jiffies + msecs_to_jiffies(5));800 return;801 }802 803 /* If failure or stage 1, command is complete */804 if (fail || cmd->stage != 0) {805 smu_i2c_complete_command(cmd, fail);806 return;807 }808 809 DPRINTK("SMU: going to stage 1\n");810 811 /* Ok, initial command complete, now poll status */812 scmd->reply_buf = cmd->pdata;813 scmd->reply_len = sizeof(cmd->pdata);814 scmd->data_buf = cmd->pdata;815 scmd->data_len = 1;816 cmd->pdata[0] = 0;817 cmd->stage = 1;818 cmd->retries = 20;819 smu_queue_cmd(scmd);820}821 822 823int smu_queue_i2c(struct smu_i2c_cmd *cmd)824{825 unsigned long flags;826 827 if (smu == NULL)828 return -ENODEV;829 830 /* Fill most fields of scmd */831 cmd->scmd.cmd = SMU_CMD_I2C_COMMAND;832 cmd->scmd.done = smu_i2c_low_completion;833 cmd->scmd.misc = cmd;834 cmd->scmd.reply_buf = cmd->pdata;835 cmd->scmd.reply_len = sizeof(cmd->pdata);836 cmd->scmd.data_buf = (u8 *)(char *)&cmd->info;837 cmd->scmd.status = 1;838 cmd->stage = 0;839 cmd->pdata[0] = 0xff;840 cmd->retries = 20;841 cmd->status = 1;842 843 /* Check transfer type, sanitize some "info" fields844 * based on transfer type and do more checking845 */846 cmd->info.caddr = cmd->info.devaddr;847 cmd->read = cmd->info.devaddr & 0x01;848 switch(cmd->info.type) {849 case SMU_I2C_TRANSFER_SIMPLE:850 cmd->info.sublen = 0;851 memset(cmd->info.subaddr, 0, sizeof(cmd->info.subaddr));852 break;853 case SMU_I2C_TRANSFER_COMBINED:854 cmd->info.devaddr &= 0xfe;855 fallthrough;856 case SMU_I2C_TRANSFER_STDSUB:857 if (cmd->info.sublen > 3)858 return -EINVAL;859 break;860 default:861 return -EINVAL;862 }863 864 /* Finish setting up command based on transfer direction865 */866 if (cmd->read) {867 if (cmd->info.datalen > SMU_I2C_READ_MAX)868 return -EINVAL;869 memset(cmd->info.data, 0xff, cmd->info.datalen);870 cmd->scmd.data_len = 9;871 } else {872 if (cmd->info.datalen > SMU_I2C_WRITE_MAX)873 return -EINVAL;874 cmd->scmd.data_len = 9 + cmd->info.datalen;875 }876 877 DPRINTK("SMU: i2c enqueuing command\n");878 DPRINTK("SMU: %s, len=%d bus=%x addr=%x sub0=%x type=%x\n",879 cmd->read ? "read" : "write", cmd->info.datalen,880 cmd->info.bus, cmd->info.caddr,881 cmd->info.subaddr[0], cmd->info.type);882 883 884 /* Enqueue command in i2c list, and if empty, enqueue also in885 * main command list886 */887 spin_lock_irqsave(&smu->lock, flags);888 if (smu->cmd_i2c_cur == NULL) {889 smu->cmd_i2c_cur = cmd;890 list_add_tail(&cmd->scmd.link, &smu->cmd_list);891 if (smu->cmd_cur == NULL)892 smu_start_cmd();893 } else894 list_add_tail(&cmd->link, &smu->cmd_i2c_list);895 spin_unlock_irqrestore(&smu->lock, flags);896 897 return 0;898}899 900/*901 * Handling of "partitions"902 */903 904static int smu_read_datablock(u8 *dest, unsigned int addr, unsigned int len)905{906 DECLARE_COMPLETION_ONSTACK(comp);907 unsigned int chunk;908 struct smu_cmd cmd;909 int rc;910 u8 params[8];911 912 /* We currently use a chunk size of 0xe. We could check the913 * SMU firmware version and use bigger sizes though914 */915 chunk = 0xe;916 917 while (len) {918 unsigned int clen = min(len, chunk);919 920 cmd.cmd = SMU_CMD_MISC_ee_COMMAND;921 cmd.data_len = 7;922 cmd.data_buf = params;923 cmd.reply_len = chunk;924 cmd.reply_buf = dest;925 cmd.done = smu_done_complete;926 cmd.misc = ∁927 params[0] = SMU_CMD_MISC_ee_GET_DATABLOCK_REC;928 params[1] = 0x4;929 *((u32 *)¶ms[2]) = addr;930 params[6] = clen;931 932 rc = smu_queue_cmd(&cmd);933 if (rc)934 return rc;935 wait_for_completion(&comp);936 if (cmd.status != 0)937 return rc;938 if (cmd.reply_len != clen) {939 printk(KERN_DEBUG "SMU: short read in "940 "smu_read_datablock, got: %d, want: %d\n",941 cmd.reply_len, clen);942 return -EIO;943 }944 len -= clen;945 addr += clen;946 dest += clen;947 }948 return 0;949}950 951static struct smu_sdbp_header *smu_create_sdb_partition(int id)952{953 DECLARE_COMPLETION_ONSTACK(comp);954 struct smu_simple_cmd cmd;955 unsigned int addr, len, tlen;956 struct smu_sdbp_header *hdr;957 struct property *prop;958 959 /* First query the partition info */960 DPRINTK("SMU: Query partition infos ... (irq=%d)\n", smu->db_irq);961 smu_queue_simple(&cmd, SMU_CMD_PARTITION_COMMAND, 2,962 smu_done_complete, &comp,963 SMU_CMD_PARTITION_LATEST, id);964 wait_for_completion(&comp);965 DPRINTK("SMU: done, status: %d, reply_len: %d\n",966 cmd.cmd.status, cmd.cmd.reply_len);967 968 /* Partition doesn't exist (or other error) */969 if (cmd.cmd.status != 0 || cmd.cmd.reply_len != 6)970 return NULL;971 972 /* Fetch address and length from reply */973 addr = *((u16 *)cmd.buffer);974 len = cmd.buffer[3] << 2;975 /* Calucluate total length to allocate, including the 17 bytes976 * for "sdb-partition-XX" that we append at the end of the buffer977 */978 tlen = sizeof(struct property) + len + 18;979 980 prop = kzalloc(tlen, GFP_KERNEL);981 if (prop == NULL)982 return NULL;983 hdr = (struct smu_sdbp_header *)(prop + 1);984 prop->name = ((char *)prop) + tlen - 18;985 sprintf(prop->name, "sdb-partition-%02x", id);986 prop->length = len;987 prop->value = hdr;988 prop->next = NULL;989 990 /* Read the datablock */991 if (smu_read_datablock((u8 *)hdr, addr, len)) {992 printk(KERN_DEBUG "SMU: datablock read failed while reading "993 "partition %02x !\n", id);994 goto failure;995 }996 997 /* Got it, check a few things and create the property */998 if (hdr->id != id) {999 printk(KERN_DEBUG "SMU: Reading partition %02x and got "1000 "%02x !\n", id, hdr->id);1001 goto failure;1002 }1003 if (of_add_property(smu->of_node, prop)) {1004 printk(KERN_DEBUG "SMU: Failed creating sdb-partition-%02x "1005 "property !\n", id);1006 goto failure;1007 }1008 1009 return hdr;1010 failure:1011 kfree(prop);1012 return NULL;1013}1014 1015/* Note: Only allowed to return error code in pointers (using ERR_PTR)1016 * when interruptible is 11017 */1018static const struct smu_sdbp_header *__smu_get_sdb_partition(int id,1019 unsigned int *size, int interruptible)1020{1021 char pname[32];1022 const struct smu_sdbp_header *part;1023 1024 if (!smu)1025 return NULL;1026 1027 sprintf(pname, "sdb-partition-%02x", id);1028 1029 DPRINTK("smu_get_sdb_partition(%02x)\n", id);1030 1031 if (interruptible) {1032 int rc;1033 rc = mutex_lock_interruptible(&smu_part_access);1034 if (rc)1035 return ERR_PTR(rc);1036 } else1037 mutex_lock(&smu_part_access);1038 1039 part = of_get_property(smu->of_node, pname, size);1040 if (part == NULL) {1041 DPRINTK("trying to extract from SMU ...\n");1042 part = smu_create_sdb_partition(id);1043 if (part != NULL && size)1044 *size = part->len << 2;1045 }1046 mutex_unlock(&smu_part_access);1047 return part;1048}1049 1050const struct smu_sdbp_header *smu_get_sdb_partition(int id, unsigned int *size)1051{1052 return __smu_get_sdb_partition(id, size, 0);1053}1054EXPORT_SYMBOL(smu_get_sdb_partition);1055 1056 1057/*1058 * Userland driver interface1059 */1060 1061 1062static LIST_HEAD(smu_clist);1063static DEFINE_SPINLOCK(smu_clist_lock);1064 1065enum smu_file_mode {1066 smu_file_commands,1067 smu_file_events,1068 smu_file_closing1069};1070 1071struct smu_private1072{1073 struct list_head list;1074 enum smu_file_mode mode;1075 int busy;1076 struct smu_cmd cmd;1077 spinlock_t lock;1078 wait_queue_head_t wait;1079 u8 buffer[SMU_MAX_DATA];1080};1081 1082 1083static int smu_open(struct inode *inode, struct file *file)1084{1085 struct smu_private *pp;1086 unsigned long flags;1087 1088 pp = kzalloc(sizeof(struct smu_private), GFP_KERNEL);1089 if (!pp)1090 return -ENOMEM;1091 spin_lock_init(&pp->lock);1092 pp->mode = smu_file_commands;1093 init_waitqueue_head(&pp->wait);1094 1095 mutex_lock(&smu_mutex);1096 spin_lock_irqsave(&smu_clist_lock, flags);1097 list_add(&pp->list, &smu_clist);1098 spin_unlock_irqrestore(&smu_clist_lock, flags);1099 file->private_data = pp;1100 mutex_unlock(&smu_mutex);1101 1102 return 0;1103}1104 1105 1106static void smu_user_cmd_done(struct smu_cmd *cmd, void *misc)1107{1108 struct smu_private *pp = misc;1109 1110 wake_up_all(&pp->wait);1111}1112 1113 1114static ssize_t smu_write(struct file *file, const char __user *buf,1115 size_t count, loff_t *ppos)1116{1117 struct smu_private *pp = file->private_data;1118 unsigned long flags;1119 struct smu_user_cmd_hdr hdr;1120 int rc = 0;1121 1122 if (pp->busy)1123 return -EBUSY;1124 else if (copy_from_user(&hdr, buf, sizeof(hdr)))1125 return -EFAULT;1126 else if (hdr.cmdtype == SMU_CMDTYPE_WANTS_EVENTS) {1127 pp->mode = smu_file_events;1128 return 0;1129 } else if (hdr.cmdtype == SMU_CMDTYPE_GET_PARTITION) {1130 const struct smu_sdbp_header *part;1131 part = __smu_get_sdb_partition(hdr.cmd, NULL, 1);1132 if (part == NULL)1133 return -EINVAL;1134 else if (IS_ERR(part))1135 return PTR_ERR(part);1136 return 0;1137 } else if (hdr.cmdtype != SMU_CMDTYPE_SMU)1138 return -EINVAL;1139 else if (pp->mode != smu_file_commands)1140 return -EBADFD;1141 else if (hdr.data_len > SMU_MAX_DATA)1142 return -EINVAL;1143 1144 spin_lock_irqsave(&pp->lock, flags);1145 if (pp->busy) {1146 spin_unlock_irqrestore(&pp->lock, flags);1147 return -EBUSY;1148 }1149 pp->busy = 1;1150 pp->cmd.status = 1;1151 spin_unlock_irqrestore(&pp->lock, flags);1152 1153 if (copy_from_user(pp->buffer, buf + sizeof(hdr), hdr.data_len)) {1154 pp->busy = 0;1155 return -EFAULT;1156 }1157 1158 pp->cmd.cmd = hdr.cmd;1159 pp->cmd.data_len = hdr.data_len;1160 pp->cmd.reply_len = SMU_MAX_DATA;1161 pp->cmd.data_buf = pp->buffer;1162 pp->cmd.reply_buf = pp->buffer;1163 pp->cmd.done = smu_user_cmd_done;1164 pp->cmd.misc = pp;1165 rc = smu_queue_cmd(&pp->cmd);1166 if (rc < 0)1167 return rc;1168 return count;1169}1170 1171 1172static ssize_t smu_read_command(struct file *file, struct smu_private *pp,1173 char __user *buf, size_t count)1174{1175 DECLARE_WAITQUEUE(wait, current);1176 struct smu_user_reply_hdr hdr;1177 unsigned long flags;1178 int size, rc = 0;1179 1180 if (!pp->busy)1181 return 0;1182 if (count < sizeof(struct smu_user_reply_hdr))1183 return -EOVERFLOW;1184 spin_lock_irqsave(&pp->lock, flags);1185 if (pp->cmd.status == 1) {1186 if (file->f_flags & O_NONBLOCK) {1187 spin_unlock_irqrestore(&pp->lock, flags);1188 return -EAGAIN;1189 }1190 add_wait_queue(&pp->wait, &wait);1191 for (;;) {1192 set_current_state(TASK_INTERRUPTIBLE);1193 rc = 0;1194 if (pp->cmd.status != 1)1195 break;1196 rc = -ERESTARTSYS;1197 if (signal_pending(current))1198 break;1199 spin_unlock_irqrestore(&pp->lock, flags);1200 schedule();1201 spin_lock_irqsave(&pp->lock, flags);1202 }1203 set_current_state(TASK_RUNNING);1204 remove_wait_queue(&pp->wait, &wait);1205 }1206 spin_unlock_irqrestore(&pp->lock, flags);1207 if (rc)1208 return rc;1209 if (pp->cmd.status != 0)1210 pp->cmd.reply_len = 0;1211 size = sizeof(hdr) + pp->cmd.reply_len;1212 if (count < size)1213 size = count;1214 rc = size;1215 hdr.status = pp->cmd.status;1216 hdr.reply_len = pp->cmd.reply_len;1217 if (copy_to_user(buf, &hdr, sizeof(hdr)))1218 return -EFAULT;1219 size -= sizeof(hdr);1220 if (size && copy_to_user(buf + sizeof(hdr), pp->buffer, size))1221 return -EFAULT;1222 pp->busy = 0;1223 1224 return rc;1225}1226 1227 1228static ssize_t smu_read_events(struct file *file, struct smu_private *pp,1229 char __user *buf, size_t count)1230{1231 /* Not implemented */1232 msleep_interruptible(1000);1233 return 0;1234}1235 1236 1237static ssize_t smu_read(struct file *file, char __user *buf,1238 size_t count, loff_t *ppos)1239{1240 struct smu_private *pp = file->private_data;1241 1242 if (pp->mode == smu_file_commands)1243 return smu_read_command(file, pp, buf, count);1244 if (pp->mode == smu_file_events)1245 return smu_read_events(file, pp, buf, count);1246 1247 return -EBADFD;1248}1249 1250static __poll_t smu_fpoll(struct file *file, poll_table *wait)1251{1252 struct smu_private *pp = file->private_data;1253 __poll_t mask = 0;1254 unsigned long flags;1255 1256 if (!pp)1257 return 0;1258 1259 if (pp->mode == smu_file_commands) {1260 poll_wait(file, &pp->wait, wait);1261 1262 spin_lock_irqsave(&pp->lock, flags);1263 if (pp->busy && pp->cmd.status != 1)1264 mask |= EPOLLIN;1265 spin_unlock_irqrestore(&pp->lock, flags);1266 }1267 if (pp->mode == smu_file_events) {1268 /* Not yet implemented */1269 }1270 return mask;1271}1272 1273static int smu_release(struct inode *inode, struct file *file)1274{1275 struct smu_private *pp = file->private_data;1276 unsigned long flags;1277 unsigned int busy;1278 1279 if (!pp)1280 return 0;1281 1282 file->private_data = NULL;1283 1284 /* Mark file as closing to avoid races with new request */1285 spin_lock_irqsave(&pp->lock, flags);1286 pp->mode = smu_file_closing;1287 busy = pp->busy;1288 1289 /* Wait for any pending request to complete */1290 if (busy && pp->cmd.status == 1) {1291 DECLARE_WAITQUEUE(wait, current);1292 1293 add_wait_queue(&pp->wait, &wait);1294 for (;;) {1295 set_current_state(TASK_UNINTERRUPTIBLE);1296 if (pp->cmd.status != 1)1297 break;1298 spin_unlock_irqrestore(&pp->lock, flags);1299 schedule();1300 spin_lock_irqsave(&pp->lock, flags);1301 }1302 set_current_state(TASK_RUNNING);1303 remove_wait_queue(&pp->wait, &wait);1304 }1305 spin_unlock_irqrestore(&pp->lock, flags);1306 1307 spin_lock_irqsave(&smu_clist_lock, flags);1308 list_del(&pp->list);1309 spin_unlock_irqrestore(&smu_clist_lock, flags);1310 kfree(pp);1311 1312 return 0;1313}1314 1315 1316static const struct file_operations smu_device_fops = {1317 .read = smu_read,1318 .write = smu_write,1319 .poll = smu_fpoll,1320 .open = smu_open,1321 .release = smu_release,1322};1323 1324static struct miscdevice pmu_device = {1325 MISC_DYNAMIC_MINOR, "smu", &smu_device_fops1326};1327 1328static int smu_device_init(void)1329{1330 if (!smu)1331 return -ENODEV;1332 if (misc_register(&pmu_device) < 0)1333 printk(KERN_ERR "via-pmu: cannot register misc device.\n");1334 return 0;1335}1336device_initcall(smu_device_init);1337